Google Play Music update adds option to listen to songs directly in search
Only the first three search results are playable, but you can tap on the rest to view the listing in a separate window. Apparently, the new feature is available in the latest 7.9 and 7.10 versions of Google Play Music for Android, but it might not be available to everyone yet.
Keep in mind that the new option has been implemented in addition to the standard Search page of the Android app, so you can now use both depending on the situation.
source: Google Play via 9to5Google
Things that are NOT allowed: